THE INTERLUDE OF CANCER 141
3. Trophoblastomata: Cancer and Sarcoma (malignant neoplasms).—Pathological manifestations of the asexual portion (trophoblast) of the life-cycle. They are not known to differentiate functional gametes, eggs or sperms. They never include or repeat any part of an embryo. They are never composed of somatic (“ embryonic “) cells, though they may mimic such, or even resemble no other cells in the body. As Fleischmann, Paget, and Bland-Sutton pointed out, they are “imitation tissues.” They exhibit powers of unlimited growth and increase, and they nourish themselves by eroding and destroying normal cells and tissues in a manner exactly like that of the trophoblast of normal gestation, and by means of a ferment acting intracellularly—viz., malignin.
As the two latter divisions are made up of malignant tumours, it is for them, and not for the members of the first group, that the enzyme treatment is intended.
In the foregoing simple story I have endeavoured to the best of my ability to give in outline some idea of the course and nature of my scientific work and conclusions since the days of May-June, 1888, when I worked on the shores of Black Lake, New York. Much has happened since then, not only in my own little field of work, but outside of it. It is since that time—that is, in 1889—that Hubrecht set up the name “trophoblast” to replace with a different significance the older term “chorion.” Long after then came the period of my germ-cell researches, not yet completed. These have, however, extended so far that they are revolutionizing embryology. In the light they throw on phenomena, the old Wolffian idea of epigenesis, and the allied RemakCohnheim hypothesis of embryonic “rests” as the sources of tumours, along with many other things, become memories of the past in science. The night is far spent ;